Guide attachment for sh eet-metal-cutting machines



(No Model.) 2 Sheets-Sheet 1.

T P. H. BURNHAM. GUIDE ATTACHMENT FOR SHEET METAL GUTTING MACHINES.

Patented Dec. 2, 1890.

(No Model.) 2 Sheets-Sheet 2. F. H. BUB-NHAM.

GUIDE ATTACHMENT FOR SHEET METAL CUTTING MACHINES.

No. 441,931." Patented Dec. 2, 1890.

UNITED STATES PATENT OFFICE.

FRANK ll. BURNHAM, OF BRIDGTON, MAINE.

GUIDE ATTACHMENT FOR SHEET-METAL-CUTTING MACHINES.

SPECIFICATION forming part of Letters Patent No. 441,931, dated December 2, 1890.

Application filed June 30, 1890. Serial No. 357,318. (No model.)

To all whom, it may concern.-

- Be it known that I, FRANK H. BURNHAM,a citizen of the United States, residing at Bridgton, in the county of Cumberland and State of Maine, have invented a new and useful I1nprovement in Guide Attachments for Sheet- Metal-Cutting Machines, of which the following is a full, clear, and exact specification.

In cutting sheet metals-such as tops and bottoms for tin cansby the use of the presses known as the Ferracute and the Bliss & \Villiams machines it has been the practice for the operator to hold and guide the sheet of tin to be cut by hand, his eye being his guide for its position. By this method it is a matter of care and requires skill and experience on the part of the operator to so place the sheet of metal under the die as to get the largest number of tops or bottoms from the sheet and at the same time to so cut the tin that between the metal out for the tops or bottoms the tin in the spaces will be left regular in size, so that studs may be out from the material so left in the interspaces. Great care was also required to make the circle of the tops and bottoms complete without clipping and at the same time to effect the aboveenumerated objects.

The object of my invention is to furnish a guide for the sheet of metal so being cut, so that the operation may be much quicker than heretofore and certainty of position of the sheet of metal under the cutting-die will be secured and the largest number of circular pieces of the desired size produced from the sheet, with the intcrspaces of regular size, from which studs can be afterward cut.

In the accompanying drawings, Figure 1 is a plan View of the attachment, showing in dotted lines the sheet of metal with the openings left therein after the tops and bottoms have been cut out. Fig. 2 is a front elevation of the same, and Fig. 3 is a transverse section on line 47c 00 of Fig. 1.

In the drawings a bracket or portion of the frame of the press is shown at A. To this is secured by slotted brackets 1 and suitable bolts a horizontal plate or frame 13. This frame is of elongated form, and at its ends it has bearings 2 for round rods or bars 3, which extend longitudinally and constitute the ways or tracks upon which the plate-carrying frame is adjusted. This carrier consists of a horizontal plate C, having boxes or bearings 4:, screwed on its under side, which embrace the tracks or ways 3, and are fitted to slide thereon, and this sliding movement allows the carrier to be adjusted beneath the die, (not shown,) so as to present different portions of the sheet-metal plate held by the carrier to the cutting-die. The carrier further consists of a supplemental frame made up of bars 0 0, extending laterally of the main frame 0, which bars are connected at their front ends by a bar 0. This supplemental frame is intended to directly hold the sheet-metal plate from which the tops and bottoms are cut,- and it extends con siderably past the main frame 0 in a lateral direction, so that the plate can be out without obstruction from the main supporting parts of the device, the cutting being done alongside the edge of the main plate 0 in the space inclosed by the bars 0 C. These bars carry guide-ribs 6 6 screwed thereto, against which the edges of the plate rest, and at the front ends they have upturned clips 7 7, which confine the rear edge of the plate. The supplemental frame is adjustable laterally in order to bring first one portion of the plate beneath the die for forming a row of tops and bottoms, as X, and then it is moved to allow the die to cut the second row marked 'y. This lateral movement is guided by the clips 8 8, secured to the main frame 0 and engaging with the bars 0'. The amount of adjustment either of the main frame G or the supplemental frame must be accurate to insure good and rapid work, and I have provided means whereby the frames may be adjusted step by step to form the tops and bottoms in proper succession.

A lug is cast with the main frame C, anda lever D is pivoted to this, the front end of which carries a pin adapted to enter a series of holes 9. The distance between the centers of these holes is the same as the distance from center to center of the cuts made by the cutting-die, and these distances are regulated so that the sheet of material will be cut without Waste, only a very thin portion being left between the cuts. The holes are preferably formed in an adjustable bar E, held to the supporting-frame by screws passing through slots 10 in the bar. The lever is acted upon by a spiral spring 11, bearing against its handle 12 and tending constantly to force the pin inward, so that in adjusting the carriage longitudinally it is only necessary to Withdraw the pin from the hole by pressing upon the handle of the spring-lever, and then by shifting the carrier along the Ways the pin will snap into the next hole and retain the carrier in place for the next cut of the die, after which the same action is gone through again until an entire row of cuts has been made. After one row of bottoms or tops has been thus produced, the supplemental frame of the carrier is shifted laterally, so that the second row y can be cut, and for doing this an operating-lever F is pivoted to the main carrier-frame and has a pin 20, which enters a slot w in the bar 0, which is of proper length to secure the desired adjustment from row to row, theadjustmentbeing determined by the pin 20 striking the end walls of the slot. A sheet of tin may be used sufficiently long to form four rows of tops, and in cutting this the operator inserts first one end and then the other, keeping hold of the projecting edge to steady the sheet. In order to economize the material the centers of the openings in the second row of openings do not come directly opposite the centers of the first row of openings, but opposite the space between the peripheries of the other set. In order to'secure this action it is necessary to change the position of the holes 9 in relation to the die and the stationary parts of the press, and for this purpose the holes are made in the longit-udinally-adjustable bar E, before mentioned. The position of this bar is altered by means of a lever G, pivoted on a bracket depending from the supporting-frame, being connected with the bar E by a link lfi'and having a springleverpivoted thereon the catch-pin 13 of which is adapted to enter either one of the holes 14 15 in the bracket, the hole 15 determining the the .main carrier-frame movable thereon, and

the supplemental carrier-frame extending laterally beyond the sides of the main frame and movable on said frame, substantially as described.

2. In combination, the supporting-frame having the Ways 3 3, the main carrier-frame movable thereon, the supplemental frame extending laterally over the main carrier-frame to move thereon, and the clips 8 S for holding the supplemental frame to the main carrier-frame, substantially as described.

In combination, the supporting-frame, the movable carrier-frame supported thereby, and means for determining the position of the carrier-frame at different points, consisting of the catch engaging with suitable openings on the frame.

I. In combination, he supporting-frame, the movable carrier-frame, the supplemental frame adjustable laterally thereon, the catch for the main carrier-frame, the adjustable bar E, having openings to receive the catch-pin, and means for adjusting the bar, substantial] y as described.

5. In combination, the supporting-frame, the movable carrier-frame, the supplemental frame adjustable laterally thereon and having a slotted part O, and means for operating the supplemental frame, consisting of the lever pivoted to the main carrier-frame and having a pin working in the slot of the bar 0, substantially as described.

FRANK H. BURNIIAM.

Witnesses:

FRANK P. BENNETT, GEORGE N. BURNHAM. 

